1. Field of the Invention
The present invention relates to an easy-to-operate cylindrical lock. In particular, the present invention relates to a cylindrical lock that is easy-to-operate for people that are handicapped in the hands or without hands.
2. Description of the Related Art
FIGS. 1 through 3 of the drawings illustrate a conventional cylindrical lock comprising an inner assembly 1, an outer assembly 2, and a latch mechanism 3. The inner assembly 1 includes an inside lever handle 11, an inside rose 12, an inside rose liner 13, and an inside spindle 15. The outer assembly 2 includes an outside lever handle 21, an outside rose 22, an outside rose liner 23, and an outside spindle 25. Two engaging posts 24 are mounted to an inner side of the outside rose liner 23.
The latch mechanism 3 is mounted in a door 8 and includes a housing 30 and a latch bolt 31. A cam 32 is rotatably mounted in the housing 30 and operably connected to the latch bolt 31 such that rotation of the cam 32 causes retraction of the latch bolt 31. The cam 32 includes a square spindle-engaging hole 321 for receiving an end of the inside spindle 15 and an end of the outside spindle 25 such that rotation of either lever handle 11, 21 causes rotation of the cam 32. The housing 30 includes two engaging holes 33 and 34 through which the engaging posts 24 respectively extend, and two screws 14 are extended through holes 16 in the inside rose liner 13 into screw holes in the engaging posts 24, thereby securing the rose liners 13 and 23 together and engaging the inner and outer assemblies 1 and 2 with the latch mechanism 3.
The lever handle 11, 21 allows easy operation for a person that is handicapped in the hands or without hands. FIG. 2 is a sectional view of the lock in a latched state, and FIG. 3 is a sectional view of the lock in an unlatched state. Unlatching of the lock is attained when the lever handle 11, 21 is moved through 45 degrees. Nevertheless, rotation of the lever handle 11, 21 is a movement in a lower portion of a circle in which the arm of the user is moved inward. More specifically, it is not easy to apply force in such a posture. Further, a returning force is generated by a return spring in the lock when the lever handle 11, 21 reaches its end of the unlatching travel. This further increases difficulty to the user that is handicapped in the hands or without hands. Further, the engaging strength between the inner and outer assemblies 1 and 2 and the latch mechanism 3 by the engaging posts 24 is not strong enough and is thus apt to be destroyed.
An object of the present invention is to provide a cylindrical lock having an inside lever handle and an outside lever handle that incline upward and are at 45 degrees with a horizontal axis such that a person without hands may operate either lever handle easily.
Another object of the present invention is to provide a cylindrical lock having a reinforcing plate to reinforce the structure while allowing easy operation of either lever handle.
A lock in accordance with the present invention includes an inner assembly, an outer assembly, and a latch mechanism. The inner assembly includes an inside lever handle, an inside rose, an inside rose liner, and an inside spindle. The outer assembly includes an outside lever handle, an outside rose, an outside rose liner, and an outside spindle. Two engaging posts extend from the outside rose liner. The latch mechanism includes a housing and a latch bolt. The latch bolt is operably connected to the inside lever handle and the outside lever handle such that 45xc2x0 rotation of either one of the inside lever handle and the outside lever handle causes retraction of the latch bolt into the housing.
A reinforcing plate includes two pegs respectively extending through two positioning holes of the housing. The reinforcing plate further includes a central hole through which the outside spindle extends. The reinforcing plate further includes a pair of slots through which the engaging posts extend. Two fasteners are extended through the inside rose liner and engaged with the engaging posts. Each of the inside lever handle and the outside lever handle are located in a position that inclines upward and at 45 degrees with a horizontal axis.
The reinforcing plate may further include another pair of slots. The engaging posts are selectively engaged in one of the two pairs of slots so as to be used with one of a left-handed door and a right-handed door.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.